head-to-head

Anthropic: Claude Opus 5.5 (batch) vs Google: Gemini 3.8 Flash

Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-10-04.

Anthropic: Claude Opus 5.5 (batch) Google: Gemini 3.8 Flash
Vendoranthropicgoogle
Quality Score100100
Benchmark Score100.069.0
Input Price$2.00/M$0.75/M
Output Price$10.00/M$3.75/M
Context Window1,000,0001,048,576
Max Output128,00065,536
Tool Calling✓✓
Structured Output✓✓
Reasoning Mode✓✓
Vision✓✓
Audio-✓
Benchmark Scores
ai_index95.167.5

The verdict

For a sample job of 1 million input tokens and 250,000 output tokens, Gemini 3.8 Flash costs $1.69 and Claude Opus 5.5 (batch) costs $4.50, so Gemini 3.8 Flash is about 2.7 times cheaper for the same work.

Both take in a similar amount of text: 1,000,000 and 1,048,576 tokens, about 1,500 and 1,573 pages.

Only Gemini 3.8 Flash offers audio input and video input.

On our blended benchmark score Claude Opus 5.5 (batch) leads 100.0 to 69.0.

Across the 20 tasks where they differ, Claude Opus 5.5 (batch) scores higher on 16 (SQL Generation, Code Review, Code Refactoring and others), Gemini 3.8 Flash on 4 (Code Completion, JSON Extraction, Bulk Data Labeling and others).

Pick Claude Opus 5.5 (batch) if you need benchmark performance or the stronger all-round task scores; pick Gemini 3.8 Flash if you need lower cost, audio input or video input.

Costs use current list prices per million tokens; page counts assume about 0.75 words per token and 500 words per page.

Who wins by task?

TaskAnthropic: Claude Opus 5.5 (batch)Google: Gemini 3.8 Flash
SQL Generation 144 141
Code Review 150 144
Code Completion 119 132
Code Refactoring 151 146
Bug Fixing 154 148
Unit Test Generation 135 132
Code Documentation 138 137
Regex Writing 127 125
CI/CD Pipelines 131 128
Frontend Component Design 133 130
Data Analysis 138 134
CSV / Spreadsheet Cleanup 136 136
ETL Scripting 141 137
JSON Extraction 121 131
Bulk Data Labeling 118 128
OCR / Document Parsing 135 134
Table Extraction from PDFs 135 134
Long-Document Summarization 152 148
Short-Form Summarization 118 126
Blog Post Writing 132 129

Scores reflect capability match + benchmark data + pricing for each task. Methodology →

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